you are right, many authors do not comment back and do not upvote comments. this annoys me. If someone has the deciency to spend their time engaging with you, the least you can do is offer a little time back. But these are personal standards I have and not everyone is the same.
You are also correct about having to start following people that you may not be really interested in. Maybe I should do a post addressed to the other side of this, those earning more that don't thank their followers.
Maybe it's just the factor that I rarely get much more than one or two comments when I post, so responding is just a matter of paying attention.
The other hand of following people you may not be otherwise interested in is that occasionally, you will come across some other the few shining lights. People who built a following with little to no use of bots, who respond to many or most who want to engage in the discussion. People who, otherwise, would not have looked in their direction twice.